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Cheese preservation has become a major issue for the global cheese industry due to microbial spoilage and the effects of chemical preservatives on human health. Consumer health and environmental awareness have motivated researchers to introduce cheese products that contemplate safety, minimal processing, eco-labels, and clean labels. Preservation strategies include a) advanced technologies comprising non-thermal processing (high pressure, cold plasma, pulsed light, ultrasound) and packaging technologies (bioactive films, coating, and modified atmospheric packaging), b) direct incorporation of natural antimicrobial agents, such as mycocins, endolysins, lactic acid bacteria and their bacteriocins and c) application of various plant extracts, essential oils and propolis. Advanced technologies have shown broad-spectrum antimicrobial action with a minimal adverse effect on cheese quality. Methods such as the direct addition of plant extracts negatively affect cheese texture, sensory and physicochemical properties. However, encapsulated and film forms are known to minimize these drawbacks. This review comprehends the sustainable cheese preservation strategies, their effectiveness in shelf-life extension, and physiochemical and quality attributes of cheese post-preservation. Overall, this review can benefit the cheese industry by enhancing market value, consumer satisfaction, and environmental well-being. • Sustainable strategies have shown substantial efficiency in cheese preservation. • Nonthermal processing and active packaging, have minimal adverse effects on cheese quality attributes. • Plant extract and propolis improve safety but may interfere with the sensory and textural properties of cheese. • Combining advanced technology with appropriate natural antimicrobial agents contributes to efficient preservation. • Examination of physicochemical properties have been established to validate the efficacy of preservation methods. [ABSTRACT FROM AUTHOR]

Summary: Thirty‐four different ready‐to eat (RTE) vegetable salads were inoculated with a cocktail of three Salmonella enterica strains, and stored under a modified atmosphere for up to 168 h at 4, 7, 12 and 16°C. Eighteen (18) of the salad samples comprised of two or more vegetable ingredients (also referred to as MV RTE salads), and 16 were made up of single vegetable ingredients (SV RTE salads). Generally, the growth potential of inoculated S. enterica varied depending on temperature and type of RTE vegetable salad. The higher temperature was generally more favourable for the growth of S. enterica. Among all 34 salad samples, 5, 11, 18 and 24 salad samples supported the growth of Salmonella at 4, 7, 12 and 16°C, respectively. All salads consisting of multiple vegetable ingredients except two: one comprised of carrots, lettuce and beetroot and another comprised of white cabbage and purple cabbage, supported the growth of Salmonella at high temperatures (either 12 or 16 or both 12 and 16°C). Although the growth of Salmonella was variable in the different types of RTE salads, and growth was generally low at 4°C, Salmonella exhibited consistently minimal growth in some vegetable salads such as those comprised of carrots, lettuce and beetroot, carrots, beetroots, cabbage and cucumber, as well as one comprised of beetroot and corn at all temperature conditions tested. [ABSTRACT FROM AUTHOR]

Background Raw materials such as cocoa, milk powder, sugar, and starch are widely used in the formulation of a wide variety of processed foods. The unit operations applied during their production vary according to their specific properties, technological advances and needs, which undoubtedly affect the microbial composition found in these raw materials. The microbial composition of these raw materials is known to consist mainly of spores of bacteria, which are known to withstand harsh food processing conditions. Scope and research This article aims to discuss data available on the diversity of spore forming bacteria in selected raw materials (cocoa, milk powder, sugar, starch). These raw materials are contaminated mainly by spore forming bacteria, which can germinate and be a concern in products made with these ingredients. In addition, this review presents data gaps and studies needed to establish the fate of spore forming bacteria throughout the production chain of specific raw materials. Key findings and conclusions The review of literature conducted in this study indicates that data on the effects of processing and diversity of spore forming bacteria in sugar and starch are much scarcer compared with cocoa and milk powders. Thus, cutting-edge approaches combining quantitative data with metagenomics could be used to improve our knowledge on the fate and diversity of spore forming bacteria in raw materials. These approaches can be employed to guide further developments that are aimed at enhancing food safety and controlling food spoilage caused by spore forming bacteria. [ABSTRACT FROM AUTHOR]

Some species from Aspergillus section Nigri are morphologically very similar and altogether have been called A. niger aggregate. Although the species included in this group are morphologically very similar, they differ in their ability to produce mycotoxins and other metabolites and their taxonomical status has evolved continuously. Among them, A. niger and A. welwitschiae are ochratoxin A and fumonisin B 2 producers and their detection and/or identification is of crucial importance for food safety. The aim of this study was the development of a real-time PCR-based method for simultaneous discrimination of A. niger and A. welwitschiae from other species of the A. niger aggregate isolated from coffee beans. One primer pair and a hybridization probe specific for detection of A. niger and A. welwitschiae strains were designed based on the BenA gene sequences, and used in a Real-time PCR assay for the rapid discrimination between both these species from all others of the A. niger aggregate. The Real-time PCR assay was shown to be 100% efficient in discriminating the 73 isolates of A. niger / A. welwitschiae from the other A. niger aggregate species analyzed as a negative control. This result testifies to the use of this technique as a good tool in the rapid detection of these important toxigenic species. [ABSTRACT FROM AUTHOR]

Modified mycotoxins are metabolites that normally remain undetected during the testing for parent mycotoxin. These modified forms of mycotoxins can be produced by fungi or generated as part of the defense mechanism of the infected plant. In some cases, they are formed during food processing. The various processing steps greatly affect mycotoxin levels present in the final product (free and modified), although the results are still controversial regarding the increase or reduction of these levels, being strongly related to the type of process and the composition of the food in question. Evidence exists that some modified mycotoxins can be converted into the parent mycotoxin during digestion in humans and animals, potentially leading to adverse health effects. Some of these formed compounds can be even more toxic, in case they have higher bioaccessibility and bioavailability than the parent mycotoxin. The modified mycotoxins can occur simultaneously with the free mycotoxin, and, in some cases, the concentration of modified mycotoxins may exceed the level of free mycotoxin in processed foods. Even though toxicological data are scarce, the possibility of modified mycotoxin conversion to its free form may result in a potential risk to human and animal health. This review aims to update information on the formation, detection, occurrence, and toxic effects caused by modified mycotoxin. [ABSTRACT FROM AUTHOR]

This study investigated aflatoxin degradation during peanut roasting. First, peanuts contaminated with three initial aflatoxin concentrations (35, 332 and 695 μg/kg) were roasted at 180 °C for up to 20 min. The percentage of aflatoxin degradation after 20 min were 55, 64 and 81% for peanuts contaminated with aflatoxin at 35, 332 and 695 μg/kg, respectively. This difference was statistically significant (p < 0.05), showing that initial concentration influences aflatoxin reduction. Thereafter, peanut samples contaminated with an initial aflatoxin concentration of 85 μg/kg were roasted at 160, 180 and 200 °C for 5, 10, 15, 20 and 25 min, then residual concentrations of aflatoxin were determined. Roasting at 160, 180 and 200 °C resulted in an aflatoxin reduction of 61.6, 83.6 and 89.7%, respectively. This study has provided quantitative data reinforcing the fact that roasting alone is not enough to control aflatoxins in peanuts. [ABSTRACT FROM AUTHOR]

The bioethanol visibility in the global matrix of fuels, linked to ecological appeal and the possibility of using new raw materials justifies the increasing investments for the development of new processes. This fuel results from fermentation of sugars by yeasts, however the growth of exogenous microorganisms is sometimes unavoidable. The lactic acid bacteria and wild yeasts are the main contaminants, affecting yeasts’ performance and leading to negative impacts such as the formation of organic acids, polysaccharides and gummy biofilms. Further undesirable effects of the microbial contamination during bioethanol processing comprise flocculation, reduction of yeast cells viability and decrease in process yield. In extreme cases, the reduction in process yield can reach 20–30%, making the process impracticable. In this article, the impact and significance of microbial contaminants (lactic acid bacteria and wild yeasts) during fermentation of must for bioethanol production are reviewed. [ABSTRACT FROM AUTHOR]

A total of 119 samples of peanut were collected throughout the peanut production chain in São Paulo State, Brazil. The peanut samples were directly plated for determination of percentages of infection and a polyphasic approach was used to identify Aspergillus section Flavi species. Further, the potential for aflatoxin production by the isolates was tested using the agar plug technique and the presence of aflatoxins in peanuts was assessed using an immunoaffinity column followed by quantification using HPLC with reverse phase column and fluorescence detection. The limit of detection and quantification were 0.05 and 0.17 μg/kg for total aflatoxins, respectively. Four species of Aspergillus section Flavi were isolated: A. caelatus (11), A. flavus (515), A. parasiticus (17) and A. tamarii (13). All isolates of A. parasiticus were able to produce aflatoxin B and G whereas aflatoxin B was produced by 50% of A. flavus isolates. Aflatoxins were found in 12 samples at concentrations ranging from 0.3 to 100 μg/kg. The data reported in this study add information on the occurrence and biodiversity of fungi in peanuts at several stages of the production chain. The occurrence of aflatoxins is also of major relevance for continuous monitoring and assessment of likely exposure of consumers to aflatoxins through consumption of peanuts. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop a quantitative microbial risk assessment (QMRA) model to estimate the risk of illness caused by Salmonella in ready-to-eat (RTE) leafy greens, based on common practices in Brazilian processing plants. The risk assessment model considered five modules: in field, washing step, retail storage, home storage and dose-response. Fifty thousand iterations of a @Risk model built in Excel were run for each of sixty scenarios. These scenarios considered different initial pathogen concentrations, fractions of contaminated produce and chlorine concentrations. For chlorine, seven pre-set concentrations (0, 5, 10, 25, 50, 150 and 250 mg/L) and three triangular distributions were considered [RiskTriang(0,5,10 mg/L), RiskTriang(0,80,250 mg/L) and RiskTriang(10,120,250 mg/L)]. The outputs were risk of infection, estimated number of illnesses and estimated percent of illnesses arising from cross-contamination. The QMRA model indicated quantitatively that higher chlorine concentrations resulted in lower risk of illness. When simulation was done with < 5 mg/L of chlorine, most (> 96%) of the illnesses arose from cross-contamination, but when a triangular distribution with 10, 120 and 250 mg/L of chlorine was simulated, no illnesses arising from cross-contamination were predicted. Proper control of the sanitizer in the washing step is essential to reduce initial contamination and avoid cross-contamination. [ABSTRACT FROM AUTHOR]

Some Escherichia coli serotypes are important human pathogens causing diarrhea or in some cases, life threatening diseases. E. coli is also a typical indicator microorganism, routinely used for assessing the microbiological quality of water especially to indicate fecal contamination. The soil is a sink and route of transmission to water and food resources and it is thus important to understand the survival of enterotoxigenic E. coli strains in soil. This study monitored the survival of six E. coli strains in sandy and loam soil. Furthermore, since biochar is a commonly used soil conditioner, the study investigated the impact of biochar amendment (15%) on the survival of the E. coli strains in (biochar-amended) sandy and loam soils. Addition of biochar affected the physicochemical properties of both soils, altering potassium levels, calcium, magnesium, sodium as well as levels of other metal ions. It increased the organic matter of loam soil from 44 g/dm3 to 52 g/dm3, and increased the pH of both sandy and loam soils. Survival and persistence of the E. coli strains generally varied according to soil type, with strains generally surviving better (P ≤ 0.05) in loam soil compared to in sandy soil. In loam soil and biochar amended loam soils, E. coli strains remained culturable until the 150th day with counts ranging between 3.00 and 5.94 ± 0.04 log CFU/g. The effects of biochar on the physicochemical properties of soil and the response of the E. coli strains to biochar amendment was variable depending on soil type. • E. coli exhibits variable survival behavior in soil based on soil type and biochar amendment. • Soil type significantly influence the survival of E. coli in soil. • E. coli strains survived for up to 150 days in loam soil. • Biochar application does not exert uniform impact on the survival of the six test E. coli strains in soil. [ABSTRACT FROM AUTHOR]

Irrigation water samples were collected from 69 farms in Sao Paulo during two rainy seasons and one dry season. Levels of culturable microorganisms were analyzed using direct plating technique, while levels of E. coli , Enterococci and Clostridium perfringens were determined using membrane filtration. Agroecosystem features including the incidence of manure stockpile, manure lagoon and livestock grazing, amongst others were observed and recorded. In the study area, groundwater (33%) was the most commonly exploited water resource for irrigating vegetables, while the least utilized resources were potable water (4%), streams (2%), lakes (2%) and domestic wastewater (2%). Other water resources exploited for irrigation in the area were farm ponds (21%), harvested rainwater (15%), canals (10%) and rivers (5%). The microbiological quality of water used to irrigate vegetables in the study area was variable depending on factors including source and treatment (chlorination) applied. The levels of culturable microorganisms recovered from the samples ranged between 11.0 and 1.7 log CFU/mL during the rainy and dry seasons, respectively, while the levels of E. coli , Enterococci and Clostridium perfringens detected in irrigation water samples were in the range of 0–6, 0 – 6.5, and 0 – 5.8 log CFU/100 mL, respectively. Irrigation water collected from farms that utilize surface waters such as canals and farm ponds generally contained higher levels of bacteria. In general, bacterial contamination varied among sources in the following order: surface water > groundwater > municipal water. Levels of bacteria detected in groundwater were comparatively low and in about 60% of the cases, for groundwater, no seasonal fluctuation in levels was observed. At the farms where seasonal fluctuations were observed for the levels of bacteria however, at least one potential source of fecal bacteria such as the presence of manure stockpile or livestock grazing was identified. • Groundwater and farm ponds were the main exploited sources for irrigation. • Seasonal variations in levels of indicator bacteria in surface water irrigation. • Irrigation water from farms that used chlorination contained low levels of E. coli. • Cattle grazing influence levels of Enterococci in groundwater irrigation water. • Manure composting is not common amongst studied farms. [ABSTRACT FROM AUTHOR]

Contaminated irrigation water is among many potential vehicles of human pathogens to food plants, constituting significant public health risks especially for the fresh produce category. This review discusses some available guidelines or regulations for microbiological safety of irrigation water, and provides a summary of some common methods used for characterizing microbial contamination. The goal of such exploration is to understand some of the considerations that influence formulation of water testing guidelines, describe priority microbial parameters particularly with respect to food safety risks, and attempt to determine what methods are most suitable for their screening. Furthermore, the review discusses factors that influence the potential for microbiologically polluted irrigation water to pose substantial risks of pathogenic contamination to produce items. Some of these factors include type of water source exploited, irrigation methods, other agro ecosystem features/practices, as well as pathogen traits such as die-off rates. Additionally, the review examines factors such as food safety knowledge, other farmer attitudes or inclinations, level of social exposure and financial circumstances that influence adherence to water testing guidelines and other safe water application practices. A thorough understanding of relevant risk metrics for the application and management of irrigation water is necessary for the development of water testing criteria. To determine sampling and analytical approach for water testing, factors such as agricultural practices (which differ among farms and regionally), as well as environmental factors that modulate how water quality may affect the microbiological safety of produce should be considered. Research and technological advancements that can improve testing approach and the determination of target levels for hazard characterization or description for the many different pollution contexts as well as farmer adherence to testing requirements, are desirable. [ABSTRACT FROM AUTHOR]

The current study was carried out to estimate the risks of infection due to consumption of RTE vegetables contaminated with Salmonella and Listeria monocytogenes in Brazil. The risk assessment model was composed of five different modules comprising the retail-consumption steps. Scenarios were simulated using prevalence and concentration levels reported in RTE vegetables in Brazil as well as considering values 10 times lower. In addition, scenarios in which temperature during transportation and storage are maintained below 5 °C were also evaluated. Models built in Excel spreadsheets were run (100,000 iterations) using @Risk software. The two outputs were risk of infection per month (probability of infection per month due to consumption of RTE vegetables) and number of infections per month (number of people that consumed RTE vegetables and get infected per month). The QMRA models predicted that the mean risk of Salmonella infection per month is 5.7E-03, while the mean risk of infection for L. monocytogenes was 8.1E-06 per month. The reduction of prevalence of Salmonella from 1.7% to 0.17% resulted in a decrease of risk of infection per month by about 6 times. In the case of L. monocytogenes, the reduction of prevalence from 2.2% to 0.22% resulted in decrease of risk of infection from 8.1E-06 to 1.0E-06. The risks and number of cases predicted in scenarios in which temperature was kept below 5 °C were reduced for both pathogens studied when compared to scenarios where this was not the case. The scenario where prevalence and concentration of pathogens was reduced and where temperature was <5 °C led to the lowest number of infections due by Salmonella and L. monocytogenes (187 and 3.3E-05 cases, respectively). The results suggest that effective mitigation strategies need to be adopted. The strict control of temperature during transportation, storage and consumption was more effective to reduce risk and number of cases due to L. monocytogenes than to Salmonella. More data is needed to improve the accuracy of risk assessment models developed. [ABSTRACT FROM AUTHOR]

This study was aimed at determining the effects of different storage scenarios on the growth potential of Salmonella strains and Listeria monocytogenes in ready-to-eat (RTE) mixes of iceberg and crisp lettuces (Lactuca sativa) and collard greens (Brassica oleracea). Vegetables were submitted to minimal processing, experimentally contaminated to achieve 10¹ and 10² CFU/g, packed under modified atmosphere and in perforated film, and submitted to the following storage scenarios: I = 100% of the shelf life (6 days) at 7°C; II = 70% of shelf life at 7°C and 30% at 15°C; III = 30% at 7°C and 70% at 15°C; IV = 100% at 15°C. Higher populations of Salmonella were observed in lettuce mixes than in collard greens; the opposite occurred with L. monocytogenes. Keeping the RTE vegetables at 15°C during the whole shelf life (scenario IV) or part of it (scenarios II and III) markedly influenced the growth of both pathogens in most of the scenarios studied (P < 0.05). Growth potentials of strains of Salmonella and L. monocytogenes were significantly different depending on the scenarios in samples packed with perforated film in comparison to those stored under modified atmosphere (P < 0.05). The findings indicate that even contamination as low as 10¹ CFU/g can lead to high populations if there is temperature abuse during storage (15°C). This study of the behavior of Salmonella and L. monocytogenes in RTE vegetables provides insights that may be useful in the development of strategies to control pathogen growth in these products. [ABSTRACT FROM AUTHOR]

Abstract: Growth potential (δ) is defined as the difference between the population of a microorganism at the end of shelf-life of specific food and its initial population. The determination of δ of Salmonella and Listeria monocytogenes in RTE vegetables can be very useful to determine likely threats to food safety. However, little is known on the behavior of these microorganisms in several RTE vegetables. Therefore, the aim of this study was to determine the δ of both pathogens in nine different types of RTE vegetables (escarole, collard green, spinach, watercress, arugula, grated carrot, green salad, and mix for yakisoba) stored at refrigeration (7°C) and abuse temperature (15°C). The population of aerobic microorganisms and lactic acid bacteria, including those showing antimicrobial activity has been also determined. Results indicated that L. monocytogenes was able to grow (δ ≥0.5 log10) in more storage conditions and vegetables than Salmonella. Both microorganisms were inhibited in carrots, although a more pronounced effect has been observed against L. monocytogenes. The highest δ values were obtained when the RTE vegetables were stored 15°C/6days in collard greens (δ =3.3) and arugula (δ =3.2) (L. monocytogenes) and arugula (δ =4.1) and escarole (δ =2.8) (Salmonella). In most vegetables and storage conditions studied, the counts of total aerobic microorganisms raised significantly independent of the temperature of storage (p <0.05). Counts of lactic acid bacteria were higher in vegetables partially or fully stored at abuse temperature with recovery of isolates showing antimicrobial activity. In conclusion, the results of this study show that Salmonella and L. monocytogenes may grow and reach high populations in RTE vegetables depending on storage conditions and the definition of effective intervention strategies are needed to control their growth in these products. [Copyright &y& Elsevier]

Abstract: The growth parameters (growth rate, μ and lag time, λ) of three different strains each of Salmonella enterica and Listeria monocytogenes in minimally processed lettuce (MPL) and their changes as a function of temperature were modeled. MPL were packed under modified atmosphere (5% O2, 15% CO2 and 80% N2), stored at 7–30 °C and samples collected at different time intervals were enumerated for S. enterica and L. monocytogenes. Growth curves and equations describing the relationship between μ and λ as a function of temperature were constructed using the DMFit Excel add-in and through linear regression, respectively. The predicted growth parameters for the pathogens observed in this study were compared to ComBase, Pathogen modeling program (PMP) and data from the literature. High R2 values (0.97 and 0.93) were observed for average growth curves of different strains of pathogens grown on MPL. Secondary models of μ and λ for both pathogens followed a linear trend with high R2 values (>0.90). Root mean square error (RMSE) showed that the models obtained are accurate and suitable for modeling the growth of S. enterica and L. monocytogenes in MP lettuce. The current study provides growth models for these foodborne pathogens that can be used in microbial risk assessment. [Copyright &y& Elsevier]

Abstract: Listeria monocytogenes is a foodborne pathogen of great concern due to the high fatality rates of listeriosis. The consumption of RTE vegetables has increased in Brazil over the last two decades, but little is known about the risks associated to the consumption of these products. This study evaluated the prevalence and counts of L. monocytogenes in 512 packages of ready-to-eat vegetables marketed in São Paulo. The isolates were characterized for their serotypes, ribotypes, positivity for virulence genes inlA, inlC and inlJ, resistance to chlorine, growth rate variability and capability to form biofilm on stainless steel (AISI 304, #4) coupons. L. monocytogenes was detected in 3.1% of the samples. Only five samples presented countable levels, with counts between 1.0×101 and 2.6×102 CFU/g. Isolates belonged to serotypes 1/2b or 4b and most were positive for genes inlC and inlJ. Ribotypable isolates were grouped into four groups: 1038 (69.4%), 19175 (11.3%), 19191 (17.7%) and 18604 (one isolate). Most isolates survived to exposure to 125ppm of a chlorine-based disinfectant for 3min. All isolates were capable to attach to the coupons, reaching counts above 4log10 CFU/cm2 and the growth rate (μ) at 25°C of the majority of the isolates varied between 0.1 and 0.2 log OD/h, but for few strains the μ was as high as 0.26log OD/h. Results of this survey indicate that RTE vegetables may be vehicles of L. monocytogenes strains with limited variation in serotype, ribotype and virulence factors but varying significantly in resistance to chlorine disinfectants, capability of forming biofilm and growth rate. Data obtained is of foremost importance to serve as baseline for the development of scientific-based policies to control the incidence of L. monocytogenes in RTE vegetables in Brazil. [Copyright &y& Elsevier]

Abstract: This study reports the implementation of GMPs in a mozzarella cheese processing plant. The mozzarella cheese manufacturing unit is located in the Southwestern region of the state of Parana, Brazil, and processes 20,000L of milk daily. The implementation of GMP took place with the creation of a multidisciplinary team and it was carried out in four steps: diagnosis, report of the diagnosis and road map, corrective measures and follow-up of GMP implementation. The effectiveness of actions taken and GMP implementation was compared by the total percentages of non-conformities and conformities before and after implementation of GMP. Microbiological indicators were also used to assess the implementation of GMP in the mozzarella cheese processing facility. Results showed that the average percentage of conformity after the implementation of GMP was significant increased to 66%, while before it was 32% (p <0.05). The populations of aerobic microorganisms and total coliforms in equipment were significantly reduced (p <0.05) after the implementation of GMP, as well as the populations of total coliforms in the hands of food handlers (p <0.05). In conclusion, GMP implementation changed the overall organization of the cheese processing unity, as well as managers and food handlers’ behavior and knowledge on the quality and safety of products manufactured. [Copyright &y& Elsevier]

Abstract: Although the production of patulin in apple fruits is mainly by Penicillium expansum, there is no information on the ability of heat resistant moulds that may survive pasteurization to produce this mycotoxin in juice packages during storage and distribution. In this study, the production of patulin by Byssochlamys spp (Byssochlamys nivea FRR 4421, B. nivea ATCC 24008 and Byssochlamys fulva IOC 4518) in cloudy and clarified apple juices packaged in laminated paperboard packages or in polyethylene terephthalate bottles (PET) and stored at both 21°C and 30°C, was investigated. The three Byssochlamys strains were able to produce patulin in both cloudy and clarified apple juices. Overall, the lower the storage temperature, the lower the patulin levels and mycelium dry weight in the apple juices (p<0.05). The greatest variations in pH and °Brix were observed in the juices from which the greatest mycelium dry weights were recovered. The maximum levels of patulin recovered from the juices were ca. 150μg/kg at 21°C and 220μg/kg at 30°C. HPLC-UV, HPCL-DAD and mass spectrometry analyses confirmed the ability of B. fulva IOC 4518 to produce patulin. Due to the heat resistance of B. nivea and B. fulva and their ability to produce patulin either in PET bottles or in laminated paperboard packages, the control of contamination and the incidence of these fungi should be a matter of concern for food safety. Control measures taken by juice industries must also focus on controlling the ascospores of heat resistant moulds. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the influence of the hot-fill water-spray-cooling process after continuous pasteurization on the number of decimal reductions (γ) and growth parameters (lag time; λ, ratio N f /N o; κ, maximum growth rate; μ) of Alicyclobacillus acidoterrestris CRA 7152 in orange juice stored at 35°C were investigated. Two different inoculum levels of A. acidoterrestris CRA 7152 (102 and 103 spores/mL) in orange juice (110Brix, pH 3.7) and a Microthermics UHT-HTST pilot plant were used to simulate industrial conditions. Results have shown that regardless of the inoculum level (102 or 103 spores/mL), the pasteurization processes were unable to cause even 1 γ. Predictive modeling using the Baranyi model showed that only κ and time to reach 104spores/mL (t104 — time to juice spoilage) were affected by the spore inoculum used (p <0.05). It has been concluded that A. acidoterrestris was able to survive the hot-fill process and to grow and spoil orange juice in 5–6days when the final storage temperature was 35°C. [Copyright &y& Elsevier]

The prevention of spoilage by Alicyclobacillus acidoterrestris is a current challenge for fruit juice and beverage industries worldwide due to the bacterium's acidothermophilic growth capability, heat resistance, and spoilage potential. This study examined the effect of storage temperature on A. acidoterrestris growth in hot-filled orange juice. The evolution of the A. acidoterrestris population was monitored under six different storage conditions after pasteurization (at 92°C for 10 s), maintenance at 85°C for 150 s, and cooling with water spray to 35°C in about 30 mm and using two inoculum levels: <101 and 101 spores/ml. Final cooling and storage conditions were as follows: treatment 1, 30°C for the bottle cold point and storage at 35°C; treatment 2, 30°C for 48 h and storage at 35°C; treatment 3, 25°C for the bottle cold point and storage at 35°C; treatment 4, 25°C for 48 h and storage at 35°C; treatment 5, storage at 20°C (control); and treatment 6, filling and storage at 25°C. It was found that only in treatment 5 did the population remain inhibited during the 6 months of orange juice shelf life. By examining treatments 1 to 4, it was observed that A. acidoterrestris predicted growth parameters were significantly influenced (P < 0.05) either by inoculum level or cooling and storage conditions. The time required to reach a 104 CFU/ml population of A. acidoterrestris was considered to be an adequate parameter to indicate orange juice spoilage by A. acidoterrestris. Therefore, hot-filled orange juice should be stored at or below 20°C to avoid spoilage by this microorganism. This procedure can be considered a safe and inexpensive alternative to other treatments proposed earlier. [ABSTRACT FROM AUTHOR]

The objective of the present study was to determine the microbiological quality of bottled mineral water marketed in commercial establishments and by street vendors and to evaluate the influence of the storage and maintenance conditions on the microbiological quality of the product. Ten samples from the same batches of five different brands of water were analyzed, for a total of 50 samples. Of the five brands analyzed, only one (brand A), when collected in a commercial establishment, complied with the legal Brazilian standards for mineral water with respect to the presence of total coliforms, fecal coliforms, and Pseudomonas aeruginosa. The remaining samples failed to comply with these microbiological standards for at least one of the parameters evaluated. The water samples obtained from street vendors were inferior !n microbiological quality to samples from the same batch that were obtained from commercial establishments. [ABSTRACT FROM AUTHOR]

Abstract: Minimally processed vegetables (MPV) may be important vehicles of Salmonella spp. and cause disease. This study aimed at detecting and enumerating Salmonella spp. in MPV marketed in the city of São Paulo, Brazil. A total of 512 samples of MPV packages collected in retail stores were tested for Salmonella spp. and total coliforms and Escherichia coli as indication of the hygienic status. Salmonella spp. was detected in four samples, two using the detection method and two using the counting method, where the results were 8.8 × 102 CFU/g and 2.4 × 102 CFU/g. The serovars were Salmonella Typhimurium (three samples) and Salmonella enterica subsp. enterica O:47:z4,z23:- (one sample). Fourteen samples (2.7%) presented counts of E. coli above the maximum limit established by the Brazilian regulation for MPV (102 CFU/g). Therefore, tightened surveillance and effective intervention strategies are necessary in order to address consumers and governments concerns on safety of MPV. [Copyright &y& Elsevier]

Enteropathogen contamination of water resources is a global concern. Several sources and routes of pathogen contamination of water resources have been identified including agriculture. Land spreading or disposal of manure/livestock wastes is a notable source of public health relevant microorganisms into water. Microorganisms can be transported from manure-amended soils into water, from where they can reach animals and humans and may cause infection. This review explores the public health relevance of manure-borne-pathogens, highlighting some of the diseases that manure associated pathogens cause. It also examines the dynamics of overland transport of pathogens into surface waters and percolation through soils into groundwater. Factors that influence the survival and transport of pathogens into respective water resources are discussed. The actual number of pathogens shed, pathogen release rate, requisite flow conditions, precipitation characteristics and pathogen inactivation potential are some general factors, examined in this review. Pathogen adaptation and survival in the soil environment is extensively discussed because soils significantly influence pathogen transfer into water. In addition to soil characteristics, environmental variables such as moisture, temperature and pH as well as soil biology are relevant aspects, considered herein. Manure and farm management practices such as manure source and type, storage and treatment, also influence the occurrence, survival and transport potential of pathogens. Optimized and recommended manure treatment techniques like composting, which has been demonstrated to satisfactorily inactivate enteric pathogens in manure are discussed. The need for proper composting by observing recommended manuring stipulations is emphasized and finally, practical strategies to protect water resources from pathogenic contamination are elucidated. [ABSTRACT FROM AUTHOR]

• Phenolic acids, stilbenes, flavanol, anthocyanin, flavonol and flavanone were detected in all flowers. • The orange flower cosmos presented the highest content of phenolic compounds. • Bioaccessibility of phenolics varied among the compounds and within the flower source. • Before in vitro digestion mini rose displayed the highest activity in FRAP and DPPH assays. • The dialyzed fraction of cravine showed the highest activity in DDPH assay. • Cosmos and mini rose are source of bioaccessible phenolics with great antioxidant activity. This study assessed the phenolics and their bioaccessibility through an in vitro digestion system coupled to a simulated intestinal barrier in eight edible flowers of distinct colors, namely mini rose, torenia, mini daisy, clitoria, cosmos, cravine, begonia and tagete. The antioxidant activity of the flowers before in vitro digestion, in their derived dialyzed and non-dialyzed fractions was evaluated using distinct approaches. All flowers presented in their composition phenolic acids, stilbenes, flavanol, anthocyanin, flavonol and flavanone, however distinct compounds and contents were found in each flower. The bioaccessibility varied among the phenolics and within the flower source (p < 0.05). Cosmos presented the highest (p < 0.05) content of phenolics and activity in ORAC assay before in vitro digestion and in dialyzed and non-dialyzed fraction; the observed activity was correlated (r = 0.9) to its major compounds, hesperidin and rutin, as well as to caftaric acid and procyanidin B2. Mini rose displayed the highest antioxidant activity in FRAP and DPPH assays before in vitro digestion; its dialyzed and non-dialyzed fraction showed the highest activity in FRAP, correlated to pelargonidin 3,5-diglucoside, catechin, epicatechin galate, epicagocatechin galate, procyanidin A2, quercitin 3-glucoside and trans- resveratrol (r = 0.9). In DPPH assay, mini rose showed the highest activity in the non-dialyzed fraction, while cravine showed the highest activity in the dialyzed fraction, which was mainly correlated to syringic acid (r = 1.0), pelargonidin 3,5-diglucoside and epicatechin (r = 0.9). Results show great variability in the phenolic composition and their bioaccessibility among the edible flowers studied. Our findings indicate cosmos and mini rose as sources of bioaccessible phenolics with great antioxidant activity. [ABSTRACT FROM AUTHOR]

Cronobacter sakazakii is a potentially pathogenic bacterium that is resistant to osmotic stress and low a w , and capable of persisting in a desiccated state in powdered infant milks. It is widespread in the environment and present in various products. Despite the low incidence of cases, its high mortality rates of 40 to 80 % amongst neonates make it a microorganism of public health interest. This current study performed a comparative assessment between current reduction methods applied for C. sakazakii in various food matrices, indicating tendencies and relevant parameters for process optimization. A systematic review and meta-analysis were conducted, qualitatively identifying the main methods of inactivation and control, and quantitatively evaluating the effect of treatment factors on the reduction response. Hierarchical clustering dendrograms led to conclusions on the efficiency of each treatment. Review of recent research trend identified a focus on the potential use of alternative treatments, with most studies related to non-thermal methods and dairy products. Using random-effects meta-analysis, a summary effect-size of 4-log was estimated; however, thermal methods and treatments on dairy matrices displayed wider dispersions - of τ2 = 8.1, compared with τ2 = 4.5 for vegetal matrices and τ2 = 4.0 for biofilms. Meta-analytical models indicated that factors such as chemical concentration, energy applied, and treatment time had a more significant impact on reduction than the increase in temperature. Non-thermal treatments, synergically associated with heat, and treatments on dairy matrices were found to be the most efficient. • Most studies related to non-thermal methods and dairy products. • A summary effect of 4-log reduction was obtained. • If considered small-study bias, a summary effect of 2-log would have been found. • Non-thermal treatments and treatments on dairy matrices were most efficient. • Chemical concentration, energy, and treatment time impacted more than temperature. [ABSTRACT FROM AUTHOR]

Ohmic heating may improve bioactive compounds and processing, ensuring food safety of beverages, liquid and pasty food, or liquid with solid pieces. Due to those traits, this study conducted a comparison between ohmic heating technology and conventional heating (CH), with a focus on assessing the impact of both methods on functional compounds (such as angiotensin-converting enzyme inhibition, α-amylase and α-glucosidase inhibition, and antioxidant activity) in both fresh and thawed raw sheep milk, which had been frozen for up to 3 mo. Different ohmic heating conditions were applied and compared to CH (3.33–8.33 V/cm vs. CH [73°C/15 s]). A total of 18 peptides with some functional activities were identified by MALDI-TOF mass spectrometry analysis. Ohmic heating samples presented the highest activities related to health, followed by CH and raw milk samples; antioxidant activity range was from 0.11% to 0.71%, antihypertensive activity ranged from 0.20% to 0.72%, and antidiabetic activity ranged from 0.21% to 0.79%. Of 51 volatile compounds detected, some were degraded by freezing, storing, and heating the sheep milk. This study showed for the first time that ohmic heating processing improved sheep milk bioactive peptides and preserved volatile compounds. [Display omitted] [ABSTRACT FROM AUTHOR]

The present work investigates the effect of chlorine stress on the subsequent growth behavior of individual Salmonella cells. A time-lapse microscopy method was used which allowed to evaluate the effect of chlorine on the division times of Salmonella individual cells and the percentage of cells able to divide after the treatment. The results showed that the percentage of cells able to divide after the chlorine treatment decreased from 92.7% for untreated cells to 43.12% and 22% for cell exposed to 127 and 150 mg/l chlorine for 3 min, respectively. The first division time of Salmonella cells was not affected by the chlorine stress at the lower tested concentration of 11 mg/l. Exposure at higher chlorine concentrations however, resulted in significantly longer and more variable division times. The mean first division times were 1.46 ± 0.61, 1.41 ± 0.53, 1.69 ± 0.59, 5.34 ± 4.03 and 19.2 ± 8.71 h after 3 min treatments with 0, 11, 61, 127 and 150 mg/l chlorine, respectively. The effect of chlorine on the second division time of the cells was milder compared to the first division. Exposure of cells to chlorine concentrations up to 61 mg/l did not affect the second division. These results indicate that the daughter cells have no "memory" of the chlorine treatment at these concentrations. For cells exposed to the highest tested chlorine concentration of 150 mg/l the mean second division time was almost 3.5 times longer compared to untreated cells indicating that potential damages of the cells caused by the chlorine treatment are not fully repaired in the second generation. The quantitative data provided by this study at the level of individual cell may lead to a better understanding of microbial resistance to chlorine and improve sanitation and decontamination procedures in the food industry. Unlabelled Image • Salmonella was exposed to different chlorine concentration (0–150 mg/l) for 3 min. • The subsequent growth of individual cells was studied using time-lapse microscopy. • Division ability after the treatment decreased with increasing chlorine concentration. • First division was affected by the chlorine stress at the higher tested concentration. • Effect of chlorine on the second division was milder compared to the first division. [ABSTRACT FROM AUTHOR]

Abstract Brazilian artisanal cheeses are characterized by the use of raw milk and in some cases, natural starter cultures, known as "pingo", as well as following simple and traditional manufacturing technology. In this study, a large-scale screening of the microbial ecology of 11 different types of artisanal cheeses produced in five geographical areas of Brazil was performed. Besides, the specific origin-related microbial signatures were identified. Clear geography- and technology-based differences in the microbiota were observed. Lactic acid bacteria dominated in all cheeses although Enterobacteriaceae and Staphylococcus also occurred in North, Northeast and Central cheeses. Differences in the lactic acid bacteria patterns were also highlighted: Streptococcus , Leuconostoc , Lactococcus and Lactobacillus were differently combined in terms of relative abundance according to product type and region of production. This study provides a comprehensive, unprecedented microbiological mapping of Brazilian cheeses, highlighting the impact of geographical origin and mode of production on microbial diversity. The results obtained will help to plan an evaluation of microbial contamination sources that will need to be studied for the improvement of cheese quality and safety. Highlights • First wide-range study of microbial diversity in Brazilian artisanal cheeses (BAC). • The cheese microbiota varied with the type of cheese and region of production. • The main genera found in the cheeses were Streptococcus , Leuconostoc and Lactococcus. • Core of bacterial genera was identified in cheeses from different production regions. • Oligotyping allowed identifying 15 Lactobacillus species in the different cheeses. [ABSTRACT FROM AUTHOR]

The study aimed to perform a meta-analysis on the fate of ochratoxin A (OTA), zearalenone (ZEN), deoxynivalenol (DON) and total aflatoxin (TAF) during steps of bread and pasta-based products processing. A total of twenty and eight articles (549 data) collected from 1983 through June 2017 were included. Some of the investigated processing such as milling and fermentation caused an increase in the concentration of DON and TAF; although they reduce the concentration of ZEN and OTA. Also, heat processing (cooking) decrease the DON, OTA, and TAF and increase the concentration of ZEN in bread. Cooking reduces the concentration of DON and ZEN in the biscuit. Cooking of pasta reduces the content of DON; however, it increases the concentration of TFA. The findings showed that the mycotoxins and their fate were influenced differently by the unit operations steps involved in the preparation of the different cereal-based products. [ABSTRACT FROM AUTHOR]

Foodborne illness resulting from the consumption of contaminated fresh produce is a common phenomenon and has severe effects on human health together with severe economic and social impacts. The implications of foodborne diseases associated with fresh produce have urged research into the numerous ways and mechanisms through which pathogens may gain access to produce, thereby compromising microbiological safety. This review provides a background on the various sources and pathways through which pathogenic bacteria contaminate fresh produce; the survival and proliferation of pathogens on fresh produce while growing and potential methods to reduce microbial contamination before harvest. Some of the established bacterial contamination sources include contaminated manure, irrigation water, soil, livestock/ wildlife, and numerous factors influence the incidence, fate, transport, survival and proliferation of pathogens in the wide variety of sources where they are found. Once pathogenic bacteria have been introduced into the growing environment, they can colonize and persist on fresh produce using a variety of mechanisms. Overall, microbiological hazards are significant; therefore, ways to reduce sources of contamination and a deeper understanding of pathogen survival and growth on fresh produce in the field are required to reduce risk to human health and the associated economic consequences. [ABSTRACT FROM AUTHOR]

Background The produced peanuts by-products are a huge challenge, but they are recognized to be a source of valuable nutrients, including natural antioxidants and antimicrobials. Antioxidants are considered as necessary ingredients in food to prevent oxidative reactions and their undesirable effects in food quality during processing and storage. However, the use of such compounds is regulated due to their harmful effects revealed by in vitro and in vivo studies. The use of natural antioxidants appears as an interesting alternative for food producers, particularly meat industries. Scope and approach Peanut skin (PS), a by-product of peanut processing in agro-industries, constitutes an under-explored source of natural antioxidants. Thus, this review was focused on both the reuse of peanuts by-products and societal health, reducing the use of synthetic antioxidants and antimicrobials. Key findings and conclusions Proanthocyanidins are the main compounds in PS that are associated with the antioxidant activity in vitro and its protective effect in meat products. Studies in recent literature strengthen the role of PS as a natural source of antioxidants wherein oxidative reactions involving mainly pigments, lipids and proteins are delayed. [ABSTRACT FROM AUTHOR]

Dairy products are the most predominant food carriers for probiotics, providing adequate therapeutic and functional benefits to the host when sufficient probiotics are maintained. Bovine milk currently dominates the global probiotic food market, but there is an increasing trend of applying nonbovine milk from other dairy animals as probiotic carrier food matrices as described in this review. Nonbovine dairy products can be considered suitable food matrices for probiotic delivery due to their excellent probiotic viability (mostly >log 7 cfu/mL or g) during shelf life, functional properties and product quality characteristics, being considered desirable and novel dairy products. [ABSTRACT FROM AUTHOR]

Higher resistance of microbial spores to high temperatures, low pH and high pressures coupled with characteristics such as good stability and rapid germination make their use extremely desirable for the innovative formulation of several probiotic foods, mainly due to the inherent technological limitations of lactic acid bacteria (LAB), which represent the main probiotic microorganisms applied in food. Probiotic spores are resistant to several processing conditions employed in the food industry, thus presenting high feasibility of application and guaranteeing the functionality of probiotic foods; in addition, they are able to maintain such characteristics throughout the shelf life of such products stored at room temperature or under refrigeration. This study presents a review of the main characteristics, technological implications, and types of consumption and health benefits of potential probiotic Bacillus spores. Spore-forming probiotics are available in different pharmaceutical forms (sachets, capsules, tablets, pills, liquid suspensions) and used in medical and veterinary fields, and more recently in the food industry. Health benefits of spore-forming probiotics should be intensively studied, evaluating their behavior in the GIT and other anatomical sites, determining the mechanisms of action involved and correlating them with the main beneficial effects on health. Spore-forming probiotics have great potential for applications in the food industry, since they present high resistance to the technological processes and physiological mechanisms of the body, which would be lethal to LAB. • Probiotic lactic acid bacteria cannot be used in all types of foods. • Bacillus probiotics are resistant to food processing conditions. • Technological implications and benefits of probiotic Bacillus are discussed. [ABSTRACT FROM AUTHOR]

Postbiotics are a relatively new concept, and studies have demonstrated important health benefits after their administration. This way, postbiotics is an emerging topic in food science. This review describes the concepts of postbiotics, demonstrates the most common processes for microbial inactivation for postbiotic production, presents the main postbiotics health effects, and discusses the current trends. Furthermore, the most studied food products are reported. The most common processes used for microbial inactivation are thermal (pasteurization, sterilization, and ohmic heating) and non-thermal (pulsed electric fields, ultrasound, irradiation, and supercritical carbon dioxide) processes. The main health effects associated with postbiotic administration are obesity prevention and control of lipidic metabolism, improvements in hydration and skin health, immune system regulation, prevention or symptom relief of chronic diseases, and improvement in constipation and intestinal health. The most studied food products are infant formulas, cereal-based products, and beverages. We highlight opportunities for studies utilizing emerging technologies for microbial inactivation, optimizing the process parameters to preserve probiotic activity after inactivation, or increasing postbiotic production. Furthermore, it is important to study new cultures with or without probiotic qualifications and identify postbiotics' conservation, processes, and stability requirements to support and facilitate industrial development. Finally, using postbiotics in food products and more clinical trials are needed to prove the technological and health effects. Nevertheless, the findings suggest that postbiotics can be applied to diet to promote health, prevent and treat diseases, and develop functional foods. • Heat treatment is the main technological process for postbiotic production. • Obesity, immune system, and microbiota are the main postbiotic targets. • The main products with postbiotics are infant formulas, cereal-based foods, and beverages. • Trends focus on new cultures, processes, and stability of postbiotics. • Isolated probiotic fractions and metabolic compounds have erroneously been described as postbiotics. [ABSTRACT FROM AUTHOR]

This study aimed to estimate the risk of staphylococcal toxin type A (SEA) poisoning from consuming Minas Frescal cheese (MFC) in Brazil. A Quantitative Microbiological Risk Assessment model was developed, focussing on the production of SEA while still in the raw material. The baseline scenario yielded a simulated mean concentration of SEA in the MFC portion of 16.20 ng. The concentration of Staphylococcus aureus in raw milk is proved to be the most influential parameter for the risk, followed by the serving size and the prevalence of toxin genes. [ABSTRACT FROM AUTHOR]

This study gathered information on the practices employed in Brazilian processing plants during production of ready-to-eat (RTE) vegetables and evaluated the effect of washing practices on the quality of RTE vegetables produced in these plants. Physicochemical analysis of water included temperature, pH, organic load and chlorine concentration and microbiological analysis included mesophilic bacteria, yeasts and molds, Enterobacteriaceae , total coliforms, Escherichia coli and Salmonella . The ten selected processing plants were clustered in three groups: 1) plants A, B, D, H and I, where washing procedures included immersion in agitated tanks during pre-washing and washing-disinfection and use of disinfectant in the pre-washing step; 2) plant E, where vegetables were washed under running water in the pre-washing step, sodium hypochlorite was used as a disinfectant agent and processing of vegetables was only manual; and 3) plants C, F, G and J, where pre-washing and washing-disinfection were performed by immersion in water, followed by a rinsing step. Chlorine was the most used chemical agent for disinfection of vegetables. A 0.2–1.2 log reduction was achieved by the practices adopted in the plants, highlighting the importance of immediate refrigeration and control measures to avoid post-processing recontamination. [ABSTRACT FROM AUTHOR]

Soft drinks, which are largely produced and consumed worldwide, are acidic beverages (pH 2.5–4.0), formulated with water, sucrose, carbonated with 1.5–5.0 volumes of CO 2 , and added or not with chemical preservatives and fruit juices. A simplified manufacturing process of soft drinks consists of water treatment, production of simple syrup, production of compound syrup, carbonation and filling. As any other food and beverage, soft drinks can be contaminated by microorganisms; however, the low pH caused by the addition of acidulants, the presence of preservatives, and the presence of CO 2 comprise major barriers to microbial growth. Because of these characteristics, filamentous fungi and some bacteria, including pathogens, do not pose spoilage and safety risks for soft drinks. On the other hand, because of their tolerance to acidic environments and CO 2 , both yeasts and aciduric bacteria can survive and deteriorate soft drinks. This review deals with the microorganisms of relevance, as well as with the factors influencing their survival and role on soft drink spoilage. [ABSTRACT FROM AUTHOR]

This study aimed to assess the bacterial microbiota involved in the spoilage of pacu (Piaractus mesopotamics), patinga (female Piaractus mesopotamics x male Piaractus brachypomus), and tambacu (female Colossoma macropomum × male Piaractus mesopotamics) during ice and frozen storage. Changes in the microbiota of three fish species (N = 22) during storage were studied through 16S rRNA amplicon-based sequencing and correlated with volatile organic compounds (VOCs) and metabolites assessed by nuclear magnetic resonance (NMR). Storage conditions (time and temperature) affected the microbiota diversity in all fish samples. Fish microbiota comprised mainly of Pseudomonas sp. , Brochothrix sp. , Acinetobacter sp. , Bacillus sp. , Lactiplantibacillus sp. , Kocuria sp., and Enterococcus sp. The relative abundance of Kocuria , P. fragi , L. plantarum, Enterococcus , and Acinetobacter was positively correlated with the metabolic pathways of ether lipid metabolism while B. thermosphacta and P. fragi were correlated with metabolic pathways involved in amino acid metabolism. P. fragi was the most prevalent spoilage bacteria in both storage conditions (ice and frozen), followed by B. thermosphacta. Moreover, the relative abundance of identified Bacillus strains in fish samples stored in ice was positively correlated with the production of VOCs (1-hexanol, nonanal, octenol, and 2-ethyl-1-hexanol) associated with off-flavors. 1H NMR analysis confirmed that amino acids, acetic acid, and ATP degradation products increase over (ice) storage, and therefore considered chemical spoilage index of fish fillets. • Microbiota in pacu, patinga and tambacu were influenced by ice and frozen storage. • Fish microbiota was dominated by Pseudomonas and Brochothrix. • VOCs studied were positive correlated with Bacillu s spp. • Metabolites (1H NMR) increased during storage can be used as spoilage biomarkers. [ABSTRACT FROM AUTHOR]

This study aimed to assess the impact of adaptation of ten strains of O157:H7 and non-O157 Escherichia coli to low pH (acid shock or slow acidification) and the effects of this exposure or not on the resistance of E. coli strains to UV radiation in orange juice (pH 3.5). The acid-shocked cells were obtained through culture in tryptic soy broth (TSB) with a final pH of 4.8, which was adjusted by hydrochloric, lactic, or citric acid and subsequently inoculated in orange juice at 4 °C for 30 days. No significant differences (p > 0.05) in survival in orange juice were observed between the serotypes O157:H7 and non-O157:H7 for acid-shocked experiments. After slow acidification, where the cells were cultured in TSB supplemented with glucose 1% (TSB + G), a significant increase (p < 0.05) in survival was observed for all strains evaluated. The D-values (radiation dose (J/cm2) necessary to decrease the microbial population by 90%) were determined as the inverse of the slopes of the regressions (k) obtained by plotting log (N/N 0). The results show that among the strains tested, E. coli O157:H7 (303/00) and O26:H11 were the most resistant and sensitive strains, respectively. According to our results, the method of acid adaptation contributes to increasing the UV resistance for most of the strains tested. • Slow acidity is more efficient than acid shock to acid adaptation of the cells. • Cell survival in orange juice differs according to the acid used after acid shock. • Resistance to UV radiation was increased by acid adaptation. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of dielectric barrier discharge (DBD) and glow discharge (glow) cold plasma treatments in color, sugars, organic acids, phenolics (concentration and bioaccessibility), antioxidant activity, volatiles, and microbiota of edible mini-roses. Plasma treatments did not affect the flowers' color, while they increased organic acids and phenolics. Flowers treated with DBD had a higher concentration of most phenolics, including hesperidin (84.04 μg/g) related to antioxidant activity, and a higher mass fraction of most volatiles, including octanal (16.46% after 5 days of storage). Flowers treated with glow had a higher concentration of pelargonidin 3,5-diglucoside (392.73 μg/g), greater bioaccessibility of some phenolics and higher antioxidant activity. Plasma treatments reduced the microbiota diversity in mini-roses. Regardless of the plasma treatment, phylum Proteobacteria, family Erwiniaceae, and genus Rosenbergiella were the dominant groups. Results indicate plasma treatments as promising technologies to improve the quality and increase phenolic and specific volatile compounds in mini-roses. [Display omitted] • Mini-roses treated by dielectric barrier (DBD) and glow discharge (glow) cold plasma. • DBD influences phenolics bioaccessibility in mini-roses. • Glow plasma treatments influence volatiles and antioxidant activity in mini-roses. • Mini roses treated with cold plasma had reduced bacterial diversity indices. [ABSTRACT FROM AUTHOR]

This study aimed to assess the behavior of endogenous microbiota (total mesophilic and psychrotrophic bacteria) during the ripening period and of L. monocytogenes and lactic acid bacteria (LAB) during storage at 5, 10, and 20 °C of artisanal Canastra cheeses packed in a silver nanoparticles packaging system using a predictive modeling approach. The tested packaging system did not influence the initial values of pH (around 5.0) or aw (around 0.95) over the storage. Based on the mathematical parameters obtained by the Weibull predictive model, the active packaging system tested did not inactivate L. monocytogenes during the storage period of artisanal Canastra cheeses. Nonetheless, the findings indicate that the polyethylene packaging system containing silver nanoparticles (3000 ppm active based on silicon dioxide and silver) did not affect endogenous bacteria of Canastra cheese during ripening and storage, which opens the opportunity for the use of this material without compromising the role of these bacteria during cheese ripening, contributing to characteristics of the product's identity. • Silver nanoparticle pack (SNP) did not kill L. monocytogenes over cheese storage. • SNP did not affect endogenous bacteria of the cheese during ripening and storage. • SNP can be used to avoid recontamination of cheese thru ripening and further steps. [ABSTRACT FROM AUTHOR]

[Display omitted] • A collection of 1396 yeast isolates from 582 artisanal cheeses was studied. • 300 of the most abundant clonemates were identified by RAPD phenotyping. • ITS1 and ITS4 typing revealed 12 genera and 28 different species. • Torulaspora delbrueckii was often detected in Canastra, Cerrado and Serro cheeses. • Yarrowia lipolytica was often detected in Coalho and Manteiga cheeses. Although less studied than bacterial biota, the presence of yeast during the artisanal cheese's production is of fundamental importance. Yeasts can prevent the growth of undesirable species in the cheese's core and surface and actively participate in the aromatic development of these products. On the other hand, reintroducing the most abundant yeast species can help mitigate potential health risks related to artisanal production. The main objective of this study was to carry out an extensive mapping of the cultivable yeast diversity present in the central Brazilian artisanal cheeses (n = 582 cheese samples). Torulaspora delbrueckii , Candida parapsilosis , Candida zeylanoides , Yarrowia lipolytica , Debaryomyces prosopidis , and Kluyveromyces lactis were amongst the 300 clusters detected, respectively. In Canastra, Cerrado, and Serro-type cheeses, the predominant species was T. delbrueckii , while in Coalho and Manteiga cheeses, Y. lipolytica was the main species detected. The findings of this study reveal the yeast cultivable diversity present in a large set of Brazilian artisanal cheeses. Furthermore, these data can serve as a basis for promoting new Brazilian origin designation policies based on microbiological data. [ABSTRACT FROM AUTHOR]